| .SDC | Stardock Corporation | Ficheiros de Cópia de Segurança | Stardock Central Download Archive | Apache OpenOffice | Apache Software Foundation |
| .SDD | Programming Sunrise | Ficheiros de Dados | Smart Diary Suite Data File | Apache OpenOffice | Apache Software Foundation |
| .SDI | Intuit, Inc. | Ficheiros de Dados | QuickBooks Data File | Apache OpenOffice | Apache Software Foundation |
| .SDP | Oracle Corporation | Ficheiros de Dados | StarOffice Presentation File | Apache OpenOffice | Apache Software Foundation |
| .SDS | Oracle Corporation | Ficheiros de Dados | OpenOffice.org Chart | Apache OpenOffice | Apache Software Foundation |
| .SDV | Pinnacle Systems Inc. | Ficheiros de Vídeo | Studio DV Project File | Apache OpenOffice | Apache Software Foundation |
| .SDW | LizardTech | Ficheiros GIS | MrSID World File | Apache OpenOffice | Apache Software Foundation |
| .SFS | Open Source | Ficheiros Compactados | Squashfs File Archive | Apache OpenOffice | Apache Software Foundation |
| .SILK | Microsoft Corporation | Ficheiros de Folha de Cálculo | Microsoft Excel Symbolic Link Format | Apache OpenOffice Calc | Apache Software Foundation |
| .SKI | Motorola | Ficheiros de Configurações | Motorola Phone Skin File | Apache OpenOffice | Apache Software Foundation |
| .SKV | Microsoft Corporation | Ficheiros de Dados | Semicolon Separated Values File | Apache OpenOffice | Apache Software Foundation |
| .SMF | Oracle Corporation | Ficheiros de Texto | StarMath Formula File | Apache OpenOffice | Apache Software Foundation |
| .SMS | Sega | Ficheiros de Jogo | Sega Master System ROM | Apache OpenOffice | Apache Software Foundation |
| .SOB | Apache Software Foundation | Ficheiros de Imagem Raster | OpenOffice.org Impress Bimap Styles File | Apache OpenOffice | Apache Software Foundation |
| .SOC | Apache Software Foundation | Ficheiros de Configurações | OpenOffice.org Configuration File | Apache OpenOffice | Apache Software Foundation |
| .SOD | id Software | Ficheiros de Jogo | Spear Of Destiny Data File | Apache OpenOffice | Apache Software Foundation |
| .SOF | Apache Software Foundation | Ficheiros de Dados | Colour Palettes And Various Style Elements File | Apache OpenOffice | Apache Software Foundation |
| .SOG | Apache Software Foundation | Ficheiros de Dados | Apache OpenOffice (OpenOffice.org) Colour Palettes | Apache OpenOffice | Apache Software Foundation |
| .SRS | Microsoft Corporation | Ficheiros de Configurações | Outlook Send/Receive Settings File | Apache OpenOffice | Apache Software Foundation |
| .STC | Adobe Systems Incorporated | Ficheiros Web | Contribute Connection Key File | Apache OpenOffice | Apache Software Foundation |
| .STD | Oracle Corporation | Ficheiros de Imagem de Vetor | Apache OpenOffice Drawing Template | Apache OpenOffice | Apache Software Foundation |
| .STE | Adobe Systems Incorporated | Ficheiros de Configurações | Dreamweaver Site Settings File | OpenOffice Writer | Apache Software Foundation |
| .STI | Oracle Corporation | Ficheiros de Dados | StarOffice Presentation Template | Apache OpenOffice | Apache Software Foundation |
| .STM | Microsoft Corporation | Ficheiros de Dados | Exchange Streaming Media File | Apache OpenOffice Calc | Apache Software Foundation |
| .STW | Oracle Corporation | Ficheiros de Texto | StarOffice Document Template | Apache OpenOffice | Apache Software Foundation |
| .SVM | Star Division | Ficheiros de Imagem Raster | StarView Metafile | Apache OpenOffice | Apache Software Foundation |
| .SVN | Apache Software Foundation | Ficheiros de Dados | Subversion Data File | Subversion | Apache Software Foundation |
| .SWX | Apache Software Foundation | Ficheiros de Texto | OpenOffice.org 1.0 Text Document | Apache OpenOffice | Apache Software Foundation |
| .SXC | Sun Microsystems | Ficheiros de Folha de Cálculo | StarOffice Calc Spreadsheet | Apache OpenOffice Calc | Apache Software Foundation |
| .SXD | ESRI | Ficheiros GIS | ArcScene Document | Apache OpenOffice | Apache Software Foundation |
| .SXG | Oracle Corporation | Ficheiros de Texto | Apache OpenOffice Master Document | Apache OpenOffice | Apache Software Foundation |
| .SXI | Oracle Corporation | Ficheiros de Dados | StarOffice Impress Presentation | Apache OpenOffice | Apache Software Foundation |
| .SXW | Oracle Corporation | Ficheiros de Texto | StarOffice Writer Document | Apache OpenOffice | Apache Software Foundation |
| .THM | Sony | Uncommon Files | Sony Ericsson Mobile Phone Theme File | Apache OpenOffice | Apache Software Foundation |
| .TIS | Acronis | Ficheiros de Cópia de Segurança | True Image Script | Apache Lucene | Apache Software Foundation |
| .TML | Odetics Broadcast | Ficheiros de Dados | AIRO Timeline File Format | Apache Tapestry | Apache Software Foundation |
| .TSV | Unknown Developer | Ficheiros de Dados | Tab Separated Values File | Apache OpenOffice | Apache Software Foundation |
| .TVX | Doug Cutting | Uncommon Files | Apache Lucene Term Vector Index File | Apache Lucene | Apache Software Foundation |
| .UOF | The Document Foundation | Ficheiros de Texto | Uniform Office Document | Apache OpenOffice | Apache Software Foundation |
| .URD | Kinook Software, Inc. | Ficheiros de Base de Dados | Ultra Recall Database File | Apache OpenOffice | Apache Software Foundation |
| .UZN | Apache Software Foundation | Ficheiros de Dados | Tesseract-Migneuzn Tool Output File | Tesseract-OCR | Apache Software Foundation |
| .VOR | Sun Microsystems | Uncommon Files | StarOffice Template | Apache OpenOffice | Apache Software Foundation |
| .VSDX | Microsoft Corporation | Ficheiros de Imagem de Vetor | Visio Drawing | Apache OpenOffice | Apache Software Foundation |
| .WAR | Oracle Corporation | Ficheiros Compactados | Java Web Archive | Apache Tomcat | Apache Software Foundation |
| .WK! | IBM | Ficheiros de Folha de Cálculo | Lotus 1-2-3 Spreadsheet | Apache OpenOffice | Apache Software Foundation |
| .WK1 | IBM | Ficheiros de Dados | Lotus Worksheet | Apache OpenOffice Calc | Apache Software Foundation |
| .WKE | IBM | Ficheiros de Folha de Cálculo | Lotus 1-2-3 Educational Version Worksheet | Apache OpenOffice | Apache Software Foundation |
| .WN | WN | Ficheiros Web | WN Web File | OpenOffice Writer | Apache Software Foundation |
| .WR! | IBM | Ficheiros de Folha de Cálculo | Lotus 1-2-3 Spreadsheet | Apache OpenOffice | Apache Software Foundation |
| .XBA | Oracle Corporation | Ficheiros Plugin | OpenOffice.org Basic Module File | Apache OpenOffice | Apache Software Foundation |
| .XCU | Apache Software Foundation | Ficheiros de Configurações | OpenOffice.org Configuration File | Apache OpenOffice | Apache Software Foundation |
| .XLB | Microsoft Corporation | Ficheiros de Configurações | Excel Toolbars File | Apache OpenOffice | Apache Software Foundation |
| .XLS | Microsoft Corporation | Ficheiros de Folha de Cálculo | Microsoft Excel 97 To 2003 Spreadsheet | Apache OpenOffice Calc | Apache Software Foundation |
| .XLSB | Microsoft Corporation | Ficheiros de Folha de Cálculo | Excel Binary Spreadsheet | Apache OpenOffice | Apache Software Foundation |
| .XLSM | Microsoft Corporation | Ficheiros de Folha de Cálculo | Microsoft Excel Open XML Macro-Enabled Spreadsheet | Apache OpenOffice Calc | Apache Software Foundation |
| .XLSX | Microsoft Corporation | Ficheiros de Folha de Cálculo | Microsoft Excel Open XML Spreadsheet | Apache OpenOffice | Apache Software Foundation |
| .Y | Microsoft Corporation | Ficheiros de Imagem Raster | Subsampled Raw YUV Image | OpenOffice Writer | Apache Software Foundation |
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